Louis maillard



L. MAILLARD. DENTAL DRILL.

(No Model.)

No. 482,558. Patented Sept. 13, 1892.

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UNITED STATES PATENT OFFICE.

LOUIS MAILLARD, OF GALT, CANADA.

DENTAL DRILL.

SPECIFICATION forming part of Letters Patent No. 482,558, datedSeptember 13, 1892.

Application filed March 31, 1892. Serial No. 427,230. (No model.)

To all whom it may concern:

Be it known that I, LOUIS MAILLARD, of the town of Galt, in the countyof Waterloo, in the Province of Ontario, Canada, have invented a certainnew and useful Improvement in Dentists Burring-Tools, of which thefollowing is a specification.

The object of my invention is to form the cutting-edges of theburring-tool in such a manner that they will each present a cleanshaving or cutting edge and have ample clearance, so that the toothsubstance will get away freely without interfering with thecutting-edges; and it consists, essentially, in thepeculiarconstruction, arrangement, and combinations of parts,hereinafter more particularly described, and then definitely claimed.

In the accompanying drawings, Figure 1 is an enlarged perspective viewof my improved dentists burring-tool. Fig. 2 is an enlarged plan ofsame.

As a rule dentists excavating or cavity burrs are made of differentshapes and sizes and shaped to out into the tooth substance Whether bydirecting the pressure on a line with the axis of rotation or at anyangle to this axis; but in the formation of burrs other than mine theircutting-edges are apt to clog and make the operation painful to thepatient. By the adoption of my device work may be done more rapidly andwill cause much less pain than any other burr with which I am familiar.

On reference to the drawings it will be seen that there are four spiralcutting-edges A. These edges are somewhat of a spiral form, and theclearing-spaces are made so as to give the cutting-edges sort of ahook-shape, enabling them to out freely, like the cuttingedges of atwist-drill. It will be observed that two of the cutting-edges A connectin the center, While the others are cut away and pointed at their lowerends, leaving clearingspaces B, which allow the chips to fall out freelywithout any danger of them clogging the cutting-edges of the instrument.Between the pointed cutting-edges and the connected ones are othercutting edges 0, running from the points of the pointed cutting-edges tothose that are connected. I do not confine myself to any particularnumber of cuttingedges; but I think that the form shown in the drawings,in which only four cutting-ed ges are employed, will be foundpreferable.

What I claim as my invention is A burr-drill having a series ofhook-shaped cutting-edges, two of which are joinedin the center andanother two terminating in points on opposite sides of the first two,and cuttingedges running between the pointed and continuedcutting-edges, substantially as described.

Galt, February 13, 1892.

LOUIS MAILLARD. In presence of W. W. LAIDLAW, WM. WALLACE, W. S.TURNBULL.

